The present invention relates to a magnetic recording medium and a method of determining whether the medium is true or false, and more particularly to an improvement in security of the magnetic recording medium.
The present invention is adapted to a magnetic recording medium, e.g., a magnetic card requiring an unfair use preventing function and a forgery and alteration preventing function.
Conventionally, the security or protection of the magnetic card, for example, is improved by a method wherein azimuth magnetic recording is carried out to prevent the forgery by a usual reader-writer, a method using a magnetic bar code, or a method using a magnetic mark.
However, the conventional methods as mentioned above require a special magnetic card and a special reader-writer, causing complication of a card system.